And eric kehjhtley



UNITED PATENT omen.

HUGH sro'rr TAYLOR, OF PRINCETON, NEW JERSEY, AND ERIC KEIGHTLEY RIDEALDF UREA-NA, ILLINOIS.

rRocEss or GENERATING HYDROGEN.

Drawing.

H To all whom it'mag concern):

Be it known that we, (1) TIUGH S'ror'r TAYLOR and (2) ERIC 'KEIGHTEEY RIDEAL, both subjects of the King of Great Britain, residing at Princeton, Urbana, in

the counties of (1) Mercer, Champaign,

' and States of '(1) New-Jersey, (2) Illinois,

have invented certain new and useful Improvements in Processes iof Generating Hy drogen, of which the following is aspecification. i

This ini' e'ntion relates to the purification of hydrogen from carbon monoxid, andto the preparatiori of hydrogen under conditions to minimize'the carbon monoxid content ofthe as.

It is well nown that in the practice ofthe various processes for generating hydrogen depending uponthe alternate oxidation of iron by steam and the reduction of the resulting iron oxid by meansofreducing gases,

in addition to the hydrogen-generating reaction 3F e+4=H O Fe O ltH V reactions likewise take place between steam .and carbon deposited in the contact material or combined with the same, these side reactions yielding carbon monoxid and carbon dioxid'. The formation of these-latter gases, which always contaminate hydrogen produced as above, may take place in accordance with any of the following equa-v Also, carbon monoxid occurs as an impurity in hydrogen from sources other than that above mentioned, and in particular it tends to accumulate in the residual or spent gases .irom catalytic processes, such for example as the hydrogenation of fats and oils; in such cases small percentages of Specification of Letters Patent. Application [ii-red October an, 1919.

Patented Apr; 4, 1922. Serial No. 331,929.

' the iron and the working temperature of' theretort. In general the ratio of steam to hydrogen rises progressively during the course "or the make, owing to the fact that at the beginning of the make steam is decomposed almost quantitatively, whereas the decomposition falls progressively throughout the run and becomes very low at the end.

On the other hand, we have found that the ratio of carbon 'mono'xid to carbon dioxid in the hydrogen as delivered decreases progressively throughout the steaming phase. This fact we attribute to the oxidation of CO to CO by the action of the increasing excess or" steam mentioned above.

Based upon our above observations, we effect the purlfication of hydrogen derived from any source and containing excessive or undesirable concentrations of carbon monoxid, by passing the impure hydrogen through the retort system, along with the steam, during asuitable period of the steaming phase. Thereby the steam, which is inoperative in the hydrogen-generating reaction, is utilized to effect the transformation of CO to CO and therefore to effect a corresponding purification of the hydrogen admitted with the steam. Or to express the matter otherwise the non-reactive and therefore non-productive excess of steam which is unavoidably present in increasing proportions throughout the steaming phase is according to this process usefully employed to oxidize (with simultaneous generation of hydrogen) carbon monoxid introduced during such phase from an outside source.

Our invention is not limited to the maintenance of any definite ratio of steam to spent or impure hydrogen, since this ratio throughout the entire steaming phase, with advantageous results so far as concerns the reduction of the carbon monoxid content of thehydrogen. The particular manner of ,operating the process will depend upon the concentration of carbon monoxid permissible for any specific use of the hydrogen.

An advantageous embodiment of the process consists in collecting the hydrogen produced during the initial steaming period, and containing as explained above relatively high concentrations of carbon monoxid, and returnin the same through the retort system during the later steaming period, when the low hydrogen production leads to the presence ofsteam in relatively v large excess, 'By operating in this way we are enabled to produce in a very simple n'ianner and in the regular operation of the known 'rocesses hydro en in which the carbonmonoxid content is decidedly lower than that of the average gas derived from theoperation as now practiced.- The yield of hydrogen inmoreove'r increased, since itis not necessary toreject so much of the firstportions of the hydrogen asis'now commonly done, or to utilize such portions if desire in accordance with anyof the well known methods.

We claim 1. In a process of generating hydrogen by alternatel V reacting with iron upon steam and red iicing the resulting iron oxid, the step which consists in introducing with the steam, durin a part at least of the steaming period, ydrogen containing carbon monoxid, whereby carbon monoxid is oxidized simultaneously -with the generation of. hydrogen. V v 1 2. Process according to claim 1, in which hydrogengenerated during an earlier phase of the steaming period and containing, carbon monoxid is returned; through the system during a later phase :of the steaming. period, whereby its carbon monoxid content diminished. a

;3. In a process ofgeneratinghydrogen by reacting with iron upon steam, the step which consistsin introducin [with the steam duringa later phase on y'fof' the steaming period, "hydrogen; containing carbon monoxid, whereby carbon monoxid 'is oxidized simultaneously with the genera tion of hydrogen.

tures.

HUGH "siroTT TAYLOR. ERIC KEIGHTLEY RIDEAL.

.In. testimony whereof, we a'flix our sign a 

